JPH09301704A - Ozone generating element and ozone generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ozone generating element and ozone generator which stably prevent the leakage of ozone with simple constitution. SOLUTION: This ozone generator is constituted by disposing a first discharger 12 consisting of dielectric layers 13, 14 contg. metallic electrodes 20 and a second discharger 16 consisting of dielectric layers 17, 18 contg. metallic electrodes 21 opposite to each other. Wirings 32, 34 for crack detection are disposed between the dielectric layers 13 and 14 and between the dielectric layers 17 and 18. When the dielectric layers crack and ozone begins to leak, the wirings 32, 34 for crack detection are disconnected. The disconnection of the wirings 32, 34 for crack detection is detected by a detecting circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ozone generator and an ozone generator, and more particularly to an ozone generator for use in water treatment of public baths or tap water, food processing, etc. The present invention relates to an ozone generating element and an ozone generating device provided.

[0002]

2. Description of the Related Art As a large-scale industrial ozone generator,
Cylindrical objects are often used. In a cylindrical ozone generator, a voltage is applied between a cylindrical glass tube having a metal electrode disposed on the back surface thereof and a stainless steel tube formed concentrically with the glass tube, whereby the glass tube A silent discharge was generated between the stainless steel tube and the stainless steel tube to generate ozone from oxygen.

Further, as a medium-sized ozone generator, a ceramic plate having metal electrodes embedded therein is opposed to each other, and a voltage is applied to the both ceramic plates to generate a silent discharge and generate ozone from oxygen. Is often used. The type using this ceramic plate is advantageous in that it can be inexpensively constructed and has high efficiency.

[0004]

However, in the prior art ozone generator for generating silent discharge between opposed ceramic plates, the ceramic plate is cracked unlike the cylindrical type using a stainless tube. Hazardous high-concentration ozone was leaked from the plant. As a countermeasure for this, it may be possible to arrange an ozone sensor to monitor the ozone concentration outside the ozone generator, but it is difficult to detect ozone stably for a long period because the ozone sensor deteriorates in performance. It was expected that it would not be possible to manufacture at low cost due to the complicated structure.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an ozone generating element and an ozone generating device capable of stably preventing leakage of ozone with a simple structure. To provide.

[0006]

In order to achieve the above object, in the present invention, a pair of discharge bodies made of ceramic layers having metal electrodes and insulating the metal electrodes from the discharge space are opposed to each other. A silent discharge type ozone generating element formed as described above, characterized in that it is provided with a crack detection wiring arranged in the ceramic layer.

In order to achieve the above object, in claim 2, a creeping discharge type ozone generating element in which a linear discharge electrode and a planar induction electrode are integrally provided via a ceramic layer is provided. The technical feature is that the wiring for crack detection provided in the layer is provided.

In order to achieve the above object, in the third aspect of the present invention, a silent discharge method is used in which a pair of discharge bodies each having a metal electrode and made of a ceramic layer for insulating the metal electrode from a discharge space are opposed to each other. And a crack detecting means for detecting cracks in the discharge body by disconnection of the crack detecting wiring. To do.

In order to achieve the above object, in claim 4, there is provided a creeping discharge type ozone generator in which a linear discharge electrode and a planar induction electrode are integrally provided via a ceramic layer. A technical feature is that a crack detection wiring arranged in a layer and a crack detection means for detecting a crack in the discharge body by disconnection of the crack detection wiring are provided.

According to the ozone generating element of claim 5, claim 1
Alternatively, in the second aspect, the crack detection wire is disposed between the same ceramic layer as the metal electrode so as to substantially surround the metal electrode.

According to the ozone generator of claim 6, claim 3
Alternatively, in the fourth aspect, the technical feature is that the crack detection wiring is disposed between the metal electrode and the same ceramic layer so as to substantially surround the metal electrode.

According to the ozone generating element of claim 7, claim 1
Alternatively, the technical feature is that the crack detection wiring is arranged between the metal electrode and a different ceramic layer.

According to the ozone generator of claim 8, claim 3
Or 4, the technical feature is that the crack detection wiring is disposed between a ceramic layer different from the metal electrode.

According to the ozone generating element of claim 9, claim 1
Alternatively, in the second aspect, the crack detecting wire is disposed on the surface of the ceramic layer as a technical feature.

An ozone generator according to a tenth aspect of the present invention is characterized in that, in the third or fourth aspect, the crack detection wiring is arranged on the surface of the ceramic layer.

According to the eleventh aspect of the present invention, in the third or fourth aspect, one of the crack detecting means detects a break in the crack detecting wiring of the pair of discharge bodies connected in series. It is a technical feature.

[0017]

In the structure of claim 1 or 2, when the ceramic layer is cracked and ozone is leaked, the crack detection wiring is broken due to the crack of the ceramic layer, and the external device is electrically disconnected. Can be recognized.

In the structure of claim 3 or 4, when the ceramic layer is cracked and ozone is leaked, the crack detection wiring is disconnected due to the crack of the ceramic layer. The break detecting means detects the disconnection of the break detecting wire.

In the fifth or sixth aspect of the present invention, since the crack detection wiring and the metal electrode are arranged between the same ceramic layers, it is not necessary to provide a ceramic layer for accommodating the crack detection wiring. Therefore, the ozone generating element and the ozone generating device can be inexpensively constructed.

In the structure of claim 7 or 8, since the crack detecting wire is arranged between the metal electrode and the ceramic layer different from the metal electrode, the crack detecting wire can be freely arranged.

In the structure of claim 9 or 10, since the crack detection wiring is arranged on the surface of the ceramic layer,
It is not necessary to provide a ceramic layer for burying the crack detection wiring. Therefore, the ozone generating element and the ozone generating device can be inexpensively constructed.

According to the eleventh aspect of the invention, since the crack detecting wirings of the pair of discharge bodies are connected in series, it is possible to detect the crack of the two discharge bodies by one crack detecting means.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments embodying the present invention will be described below with reference to the drawings. FIG. 1 shows the assembly of an ozone generating element according to the first embodiment of the present invention. The ozone generating element is composed of a plate-shaped first discharge plate (discharge body) 12 made of alumina having a tungsten metal electrode 20 arranged on its back surface, a spacer 25, and alumina having a tungsten metal electrode 21 arranged on its back surface. And a heat radiation fins (heat sinks) 22 and 24 made of aluminum are attached to the upper surface of the metal electrode 20 and the lower surface of the metal electrode 21 by soldering. There is.

The first discharge plate 12 comprises dielectric layers 13 and 14 obtained by firing two green sheets, and an opening 13a is provided in the upper dielectric layer 13. Also,
In the lower dielectric layer 14, the metal electrode 20 and the tungsten crack detection wiring 32 are arranged so as to surround the metal electrode 20. The first discharge plate 12 is provided with a terminal 20a for connecting a power supply circuit described later and the metal electrode 20 and terminals 32a, 32b for connecting a detection circuit described later and a crack detection wiring 32. Has been done.

On the other hand, the second discharge plate 16 is composed of dielectric layers 17 and 18 obtained by firing two green sheets, and the lower dielectric layer 18 is provided with an opening (not shown). . Further, on the lower surface of the upper dielectric layer 17, the metal electrode 21 and the crack detection wiring 34 are arranged so as to surround the metal electrode 21. In the second discharge plate 16,
A terminal (not shown) for connecting the power supply circuit and the metal electrode 21 and terminals 34a, 34b for connecting the detection circuit and the crack detection wiring 34 are provided. Further, the second discharge plate 16 is provided with an oxygen introducing hole 26 for taking in oxygen from the outside and an ozone introducing hole 28 for taking out ozone to the outside. This first discharge plate 1
The spacer 25 interposed between the second discharge plate 16 and the second discharge plate 16 is
An opening 25a is formed at the center to create a discharge space A. The spacer 25 is made of fluororubber having flexibility and high ozone resistance, and ozone is discharged from the discharge space A formed by the opening 25a in close contact with the first discharge plate 12 and the second discharge plate 16. Prevent it from leaking.

Next, a method of manufacturing the ozone generating element of the first embodiment will be described. First, a method of manufacturing the first discharge plate 12 will be described. 2% of MgO (weight ratio, the same below), 2% of CaO, and 4% of SiO ₂ were mixed with alumina powder, wet-milled in a ball mill for 50 to 80 hours, and then dehydrated and dried. Add methacrylic acid isobutyl ester 3 to this powder.
%, Butyl ester 3%, nitrocellulose 1%, and dioctyl phthalate 0.5% are further added, and trichlorethylene and n-butanol are added as a solvent, and mixed by a ball mill to obtain a fluid slurry. After degassing under reduced pressure, it is poured into a flat plate shape and gradually cooled, and the solvent is diffused to form alumina green sheets 13γ and 14γ having a thickness of 0.8 mm. Then, the metal electrode 20 and the crack detection wiring 3
In order to form No. 2, metallized ink is formed by making tungsten powder into a slurry. This tungsten metallized ink is screen-printed on the lower alumina green sheet 14γ so as to form a metal paste layer 20γ, 32
forms γ. Then, as shown in FIG. 2, the opening 13a is formed by punching out the central portion of the upper alumina green sheet 13γ to a size in which the peripheral portion 20b of the metal paste layer 20γ is embedded. Formed to be smaller than the paste layer 20γ), the alumina green sheet 1 is formed on the alumina green sheet 14γ.
3γ is thermocompression bonded. A through hole 30 for forming a terminal 20a for connection from a metal electrode is formed at one end of the thermocompression-bonded alumina green sheets 13γ, 14γ, and terminals 32a, 32b of a detection wiring 32 are formed. Through holes 31a and 31b for forming are formed,
The through holes 30, 31a, 31b are filled with metallizing ink for terminals, and the alumina green sheets 13γ, 14γ thus laminated are filled at 1400 ° C. to 160 ° C.
Simultaneous firing is performed in a non-oxygen atmosphere at 0 ° C. The discharge surface (opposing surface side) on the discharge space A side of the first discharge plate 12 formed by this co-firing has a surface roughness Ra of 0.4 to 0.5 μm.
m.

The surface roughness (Ra) of the first discharge plate 12 formed on the discharge space A side (opposite surface side) formed by the simultaneous firing is set to 0.2 μm or less by lapping. Here, a single-side polishing machine is used as a processing machine, and a plurality of first discharge plates 12 are attached to the disk side of the single-side polishing machine.
A polishing member using diamond of 2 to 3 μm as an abrasive is arranged on the side facing the disk, and the first discharge plate 12 attached to the disk side is pressed against the polishing member at a pressure of 1 kg / cm ² . The first discharge plate 12 is lapped and polished by rotating the disk for 1 hour.

Nickel plating is applied to the metal electrode 20 side of the first discharge plate 12 whose surface has been polished, and the radiation fins 22 are directly attached with solder or a heat conductive adhesive. In the same manner, the second discharge plate 16 is attached to the two alumina green sheets 17γ and 18γ that are laminated, and the oxygen introduction hole 26 is formed.
After forming a through hole for forming the ozone discharge hole 28 and a through hole for forming the ozone lead-out hole 28,
It is formed by simultaneous firing. Then, the discharge surface (opposing side) on the discharge space A side is lapped to have a surface roughness of 0.2.
The heat radiation fin 24 is attached to the back side of the discharge surface.

Here, as in a modified example to be described later, a crack detection wiring 32 is provided between the metal electrodes 20 and 21 and a different dielectric layer.
When disposing 34, it is necessary to dispose the crack detection wiring 32 on the dielectric layer above the metal electrode 20 and dispose the crack detection wiring 34 on the dielectric layer below the metal electrode 21.
On the other hand, in this embodiment, the same dielectric layers 14 and 17 are used.
Since the metal electrodes 20 and 21 and the crack detection wirings 32 and 34 are arranged on the upper side, the radiation fins 22 and 24 are directly attached to the metal electrodes 20 and 21 on the back surfaces of the first and second discharge plates 12 and 16, respectively. It becomes possible. Therefore, the metal electrode 2
Since 0 and 21 are kept at a low temperature, the generated ozone is not reduced to oxygen by heat, and ozone can be efficiently generated.

A mounting device 50 for mounting the ozone generating element 10 will be described with reference to FIG. 3 showing a cross section of the mounting device 50. Mounting device 50
Is made of Teflon having high ozone resistance, and has a substantially rectangular shape, and has a peripheral portion 54 with an opening 54a formed in the center.
And the lid 52 placed on the peripheral portion 54, and the ozone generating element 1 is provided in the opening 54a of the peripheral portion 54.
It is configured to hold 0. The peripheral portion 54 is formed with a step portion 54b into which the peripheral portion of the ozone generating element 10 is fitted. A concave portion 60 is formed below the oxygen introducing hole 26 of the ozone generating element 10, and a convex portion 56b directed upward is formed at a substantially central position of the concave portion 60. Ozone generator 1
Oxygen introducing hole 56 for communicating with 0 oxygen introducing hole 26
Are formed. A taper hole 62 for inserting a Teflon pipe from an external member (not shown) is formed below the oxygen introducing hole 56. The concave portion 60 and the convex portion 5
An O-ring 66, which is in contact with the ozone generating element 10 and prevents leakage of ozone, is arranged between the 6 b and 6 b. On the other hand, a concave portion 61 is formed at a position below the ozone outlet hole 28 of the ozone generating element 10, and a convex portion 58b directed upward is formed at a substantially central position of the concave portion 61.
At the center of b, the ozone lead-out hole 2 of the ozone generating element 10 is provided.
The ozone lead-out hole 58 for communicating with 8 is formed. Below the ozone lead-out hole 58, a taper hole 6 for fitting a Teflon pipe from an external member (not shown).
4 are formed.

Further, in this embodiment, as shown in FIG. 2, the opening 13a of the upper alumina green sheet 13γ is formed in a size to embed the peripheral edge portion 20b of the metal paste layer 20γ, and the lower alumina layer 13γ is formed. Green sheet 14
Attached to γ and performing simultaneous firing. That is, the peripheral portion 20b of the metal electrode 20 on the back surface of the first discharge plate 12 is embedded in the ceramic. As shown in FIG. 2, when the peripheral portion 20b of the metal electrode 20 and the opening 13a are separated from each other, the four corners 20c, 20c, 20c of the metal electrode 20, This is because a creeping discharge occurs between 20c and the other metal electrode 21 to generate ozone. Since the metal electrode 20 is arranged outside the ozone generating element, it is not desirable to generate ozone. For this reason, the peripheral portion 20b of the metal electrode 20 is
By embedding the material in ceramics, the generation of ozone is prevented. In addition, the peripheral portion of the metal electrode is similarly buried on the second discharge plate 16 side to prevent the generation of ozone.

Next, an ozone generator having an ozone leak detection circuit, which is a crack detecting means for detecting cracks in the ozone generating element of this embodiment, will be described with reference to FIG. The ozone leakage detection circuit 82 includes a gate A1, a resistor R1 and a transistor TR1, and is configured to control a relay RE1 that turns on / off the AC100V power supply to the power supply circuit 80 by the output of TR1. There is. The power supply circuit 80 connects the AC10 via the relay RE1.
When commercial power of 0 V is supplied, it is converted into a rectangular wave of several thousand V and applied between the metal electrode 20 of the first discharge plate 12 and the metal electrode 21 of the second discharge plate 16, Silent discharge is generated in the air gap between the discharge plates 12 and 16 shown in FIG. 3 to generate ozone from oxygen supplied from an oxygen gas source (not shown).

On the other hand, the gate A of the ozone leakage detection circuit 82
DC5V is supplied to one input terminal A1a of 1,
This potential is also supplied to the terminal 32a of the crack detection wiring 32 of the first discharge plate 12. The crack detection wiring 32 of the first discharge plate 12 and the crack detection wiring 34 of the second discharge plate 16 are connected in series, and the other input terminal A1b of the gate A1 has a potential stepped down by the resistor R2. Is applied.

Here, when the ozone generating element is operating normally, that is, when the first discharge plate 12 and the second discharge plate 16 are not cracked and the crack detection wires 32 and 34 are not broken. A lower potential than that of the input terminal A1a is input to the input terminal A1b of the gate A1, and the gate A1 outputs a high level. As a result, the transistor TR1 is energized, the relay RE1 is turned on, and power of AC 100 V is supplied to the power supply circuit 80.

On the other hand, when a maintenance worker accidentally hits the ozone generating element 10 with a tool and cracks any of the discharge plates 12 and 16, or the supply of oxygen from the oxygen source causes it for some reason. Delay, ozone generation element 1
When the discharge plates 12 and 16 of No. 0 abnormally generate heat and are cracked by thermal shock, ozone is leaked to the outside when the operation is continued. Here, the discharge plates 12, 1
When 6 cracks, the crack reaches the peripheral portion. In other words, a ceramic discharge plate 1
If a crack is generated in the central portion of 2, 16, this crack will almost certainly extend to the peripheral portion. Here, if the crack extends to the peripheral portion, the break detection wiring 32 or 34 is broken. Due to the disconnection of the crack detection wiring 32 or 34, D is applied to the input terminal A1b of the gate A1.
C5V comes to be added. As a result, the gate A1
Output becomes low level, the energization of the transistor TR1 is stopped, the relay RE1 is turned off, and the power supply circuit 80
The power supply to the power supply is interrupted.

In this embodiment, one ozone leak detection circuit 82 monitors the pair of discharge plates 12 and 16 for cracks. That is, one ozone leak detection circuit 82 monitored for cracks in one ozone generation element 10. However, one ozone leak detection circuit 82 monitored a plurality of ozone generation elements 1.
You can also monitor for 0 cracks. Discharge plates 12, 16, 12 ', 1 of two ozone generating elements 10, 10'
An example of the configuration of the ozone generator that monitors 6'is described with reference to FIG.

In this circuit configuration, the discharge plates 12, 16, 12 ', 1 of the two ozone generating elements 10, 10' are
Crack detection wirings 32, 34, 32 'provided in 6',
34 'are connected in series, and the potential stepped down by the resistor R2 is applied to the input terminal A1b of the gate A1. Here, the discharge plates 12, 16 of the ozone generating elements 10, 10 ',
When a crack occurs in either 12 'or 16', the crack detection wiring provided in the discharge plate is broken, and DC5V is applied to the input terminal A1b of the gate A1.
As a result, the output of the gate A1 becomes low level,
The energization of the transistor TR1 is stopped, the relay RE1 is turned off, and the power supply to the power supply circuit 80 is interrupted.

Next, a modification of the first embodiment will be described with reference to FIGS. 6 and 7. In the configuration example described above with reference to FIG. 1, the crack detection wiring 32 is disposed between the dielectric layers 14 and 13 together with the metal electrode 20, and the crack detection wiring 34 is disposed together with the metal electrode 21 in the dielectric. Layer 17,
However, in this modified example, the crack detection wiring 32 and the metal electrode 20 are arranged between different dielectric layers.

FIG. 6 shows the assembly of the ozone generating element according to the modified example. The ozone generating element is a plate-shaped first discharge plate 12 made of alumina containing the metal electrode 20.
And a spacer 25 and a plate-shaped second discharge plate 16 that houses the metal electrode 21, and heat sinks 22, 24 are provided on the upper surface of the first discharge plate 12 and the lower surface of the second discharge plate 16.
Is attached.

The first discharge plate 12 comprises dielectric layers 13, 14 and 15 obtained by firing three green sheets, a metal electrode 20 is disposed between the dielectric layers 13 and 14, and a dielectric layer is formed. A wiring 32 for detecting a crack of tungsten is arranged between the layers 13 and 15. The first discharge plate 12 is provided with a terminal 20a for connecting the power supply circuit 80 and the metal electrode 20 and terminals 32a, 32b for connecting the detection circuit 82 and the crack detection wiring 32. ing.
Similarly, the second discharge plate 16 is composed of dielectric layers 17, 18 and 19 obtained by firing three green sheets.
A metal electrode 21 is arranged between 7 and 18, and a crack detection wiring 34 is arranged between the dielectric layers 18 and 19.

FIG. 7A shows the first discharge plate 12 shown in FIG.
FIG. On the dielectric layer 13, the crack detection wiring 32 is folded and arranged so as to be parallel to the longitudinal direction of the first discharge plate 12. This modified example is easy to manufacture, and the first and second discharge plates 1 are
At the time when a minute crack that does not extend to the peripheral edge is formed in the center of 2, 16, the crack detection wirings 32, 34 are broken, so that the ozone generation element 10 can be stopped before ozone leakage occurs. There are advantages.

FIG. 7B shows a plan view of the first discharge plate 12 according to another modification. In the first discharge plate shown in FIG. 7A, the crack detection wiring 32 is arranged below the dielectric layer 15, but in the example shown in FIG. 7B, the crack detection wiring 3 is provided.
2 is exposed on the dielectric layer 13. This FIG. 7 (B)
The example shown in 1 has a feature that the manufacturing cost is low.

FIG. 8 shows the assembly of an ozone generating element 10 'according to another modification. In the configuration shown in FIG. 1, the opening 13 is formed in the first discharge plate 12 and the second discharge plate 16.
a is provided directly on the metal electrodes 20, 21, and the heat sink 22,
Although 24 is attached, in the ozone generating element shown in FIG.
The metal electrodes 20 and 21 are respectively formed into dielectric layers 13 and 18
Buried inside. Heat sinks 22 and 24 are attached to the surfaces of the dielectric layers 13 and 18, respectively. This configuration,
There is an advantage that the ozone generating element can be constructed at low cost.

Next, a second embodiment of the present invention will be described with reference to FIGS. In the above-described first embodiment, the example in which the present invention is applied to the silent discharge type ozone generating element is given, but in the second embodiment, the present invention is applied to the creeping discharge type ozone generating element. FIG. 9 shows an ozone generating element 110 according to the second embodiment. The ozone generating element 110 is composed of a first dielectric layer 113 and a second dielectric layer 114 made of ceramic.
A planar induction electrode 121 is arranged between the dielectric layer 113 and the second dielectric layer 114, and a linear discharge electrode 120 is arranged on the upper surface of the first dielectric layer 113. On the linear discharge electrode 120, a glaze layer (not shown) for preventing abrasion is arranged. In FIG. 7B, FIG.
The state which looked at the ozone generation element 110 shown to (A) from the lower side is shown. First dielectric layer 113 and second dielectric layer 11
4 between the first dielectric layer 113 and the second dielectric layer 11
The crack detection electrode 132 for detecting the crack of No. 4 is arranged together with the planar induction electrode 121. That is, the crack detection electrode 132 is arranged at the peripheral portion of the ozone generating element 110 so as to surround the planar induction electrode 121.
On the side of the second dielectric layer 114, a terminal 121 a connected to the planar induction electrode 121, and a crack detection electrode 132.
The terminals 132a and 132b connected to are exposed. Note that the planar induction electrode 121 can be formed in a mesh shape as well as a solid coating as shown in the drawing, and can also be formed in a thick line shape. When forming into a thick linear shape, it may be formed so as to extend outside the outer end of the linear discharge electrode 120 by 5 mm or more.

Regarding the mounting device 150 for mounting the ozone generating element 110, the mounting device 15 will be described.
This will be described with reference to FIG. The mounting device 150 is made of Teflon having high ozone resistance,
The peripheral portion 154 is formed in a substantially rectangular shape and has a concave portion 154a formed in the central portion, and a lid 152 placed on the peripheral portion 154. The ozone generating element 110 is provided on the concave portion 154a of the peripheral portion 154. Is configured to hold. A step portion 154 b for supporting the peripheral edge portion of the ozone generating element 110 is formed on the peripheral edge portion 154. The ozone generating element 110 is attached with the linear discharge electrode 120 facing downward as shown in FIG. 9 (B).

An oxygen introduction hole 156 and an ozone discharge hole 158 are formed in the recess 154a of the peripheral portion 154.
Below the oxygen introducing hole 156, a taper hole 162 for fitting a Teflon pipe from an external member (not shown).
On the other hand, below the ozone outlet hole 158, a tapered hole 164 for fitting a Teflon pipe from an external member (not shown) is formed.

Also in the second embodiment, the configuration of the detection circuit for detecting the disconnection of the crack detection wiring 132 and the configuration of the power supply circuit for supplying power to the ozone generating element 110 are the same as those described above with reference to FIG. Since it is similar to the one embodiment,
Illustration is omitted. Ozone generating element 1 of the second embodiment
In 10, when any of the first and second dielectric layers 113 and 114 is cracked, ozone is leaked to the outside when the operation is continued. Here, the dielectric layer 1
When a crack is formed in 13, 114, the crack reaches the peripheral portion. In other words, if a crack occurs in the central portion of the dielectric layers 113 and 114 made of ceramic, the crack almost certainly extends to the peripheral edge portion. Here, if the crack extends to the peripheral portion, the crack detection wiring 132 is broken. When a detection circuit (not shown) detects the disconnection of the crack detection wiring 132,
Stop the power supply to the power supply circuit.

In the ozone generating element 110 of the second embodiment described above, the dielectric layer 11 as shown in FIG.
4 has a radiation fin 22 attached thereto, the dielectric layer 114 is similar to the first embodiment described above with reference to FIG.
It is also possible to provide an opening portion in and to directly attach the radiation fin 22 to the planar induction electrode 121.

Next, a modification of the second embodiment will be described with reference to FIG. In the configuration example described above with reference to FIG. 9, the crack detection wiring 132 has the planar induction electrode 121.
With the dielectric layers 113 and 114,
In this modified example, the crack detection wire 132 and the planar induction electrode 121 are arranged between different dielectric layers.

FIG. 11A shows an ozone generating element according to the modified example. The ozone generating element 110 includes three plate-shaped dielectric layers 113, 114, 11 made of alumina.
5, the planar induction electrode 121 is formed on the dielectric layer 11
3 and 114, and the crack detection wiring 132 is housed between the dielectric layers 114 and 115.

FIG. 11B shows the state of the ozone generating element 110 shown in FIG. 11A as viewed from below. Under the dielectric layer 115, the crack detection wiring 132 is arranged in a folded manner so as to be parallel to the longitudinal direction of the ozone generating element 110. This modified example is easy to manufacture, and at the time when a minute crack that does not extend to the peripheral edge is formed in the center of the ozone generating element 110, the crack detection wiring 132 is broken, so that before the ozone leaks. The advantage is that the ozone generating element 110 can be stopped.

12 (A) and 12 (B) show an ozone generating element 110 according to another modification. In the ozone generating element shown in FIG. 11A, the crack detection wiring 132 is disposed below the dielectric layer 115, but in the example shown in FIGS. 12A and 12B, cracks are generated. The detection wiring 132 is exposed on the dielectric layer 114. The example shown in FIGS. 12A and 12B has a feature that the manufacturing cost is low.

Next, a third embodiment of the present invention will be described with reference to FIG. In the third embodiment, the configuration of the present invention is applied to a cylindrical ozone generating element. The ozone generating element 210 applies a voltage between a cylindrical glass tube 92 on the back surface of which a metal electrode 94 is vapor-deposited and a stainless steel tube 96 which is concentrically formed with the glass tube 92. Silent discharge is generated between 92 and the stainless tube 96 to generate ozone from oxygen.

On the metal electrode 94 of the glass tube 92, a crack detection wiring 99 is provided by vapor deposition via an insulating layer 98 formed by vapor deposition. This third
Also in the embodiment, the glass tube 9 is used for some reason.
When 2 cracks, the crack detection wire 99 is broken, and the broken wire is detected by the detection circuit described above with reference to FIG. 4, and the operation of the ozone generating element 210 is stopped.

In the above-described embodiment, the ceramic material of which the main component is alumina is used as the ceramic constituting the dielectric layer, but AlN, glass ceramic,
Various ceramic materials such as SiC, mullite, and glass ceramic can be adopted. The material of the metal paste layer forming the electrodes and the crack detection wiring may be appropriately selected according to the ceramic material, and for example, tungsten, molybdenum, copper, silver or the like can be used. In addition, in the above-described embodiment, an example in which ozone is generated from pure oxygen has been described, but the present invention can be preferably applied to an ozone generator of a type that generates air by drying air.
In the above embodiment, the detection circuit is composed of a discrete circuit, but it is possible to detect the disconnection of the crack detection wiring by various devices such as an IC.

[0056]

As described above, according to the ozone generating element and the ozone generating apparatus of the present invention, unlike the ozone sensor, secular change does not occur, so that it is possible to stably prevent the leakage of ozone for a long period of time. . In addition, ozone leakage can be prevented with a simple and inexpensive structure.

[Brief description of drawings]

FIG. 1 is a perspective view showing a manufacturing process of an ozone generating element according to a first embodiment of the present invention.

FIG. 2 is a plan view of a discharge plate of the ozone generating element shown in FIG.

FIG. 3 is a cross-sectional view showing a state in which the ozone generating element according to the first embodiment is held by a mounting device.

FIG. 4 is a circuit diagram of a power supply circuit and a detection circuit of the ozone generating element according to the first embodiment.

FIG. 5 is a circuit diagram of a power supply circuit and a detection circuit of an ozone generating element according to a modified example of the first embodiment.

FIG. 6 is a perspective view showing a manufacturing process of an ozone generating element according to a modification of the first embodiment of the present invention.

7 (A) is a plan view of a discharge plate of the ozone generating element shown in FIG. 6, and FIG. 7 (B) is a discharge according to a modification of the ozone generating element shown in FIG. 7 (A). It is a top view of a board.

FIG. 8 is a perspective view showing a manufacturing process of an ozone generating element according to another modification of the first embodiment of the present invention.

FIG. 9 is a perspective view of an ozone generating element according to a second embodiment of the present invention.

FIG. 10 is a cross-sectional view showing a state in which the ozone generating element according to the second embodiment is held by a mounting device.

FIG. 11 is a perspective view of an ozone generating element according to a modification of the second embodiment of the present invention.

FIG. 12 is a perspective view of an ozone generating element according to a modification of the second embodiment of the present invention.

FIG. 13 is a sectional view of an ozone generating element according to a third embodiment of the present invention.

[Explanation of symbols]

 10 Ozone Generating Element 12 First Discharge Plate (Ceramic Layer) 16 Second Discharge Plate (Ceramic Layer) 20 Metal Electrode 21 Metal Electrode 80 Power Circuit 82 Detection Circuit (Crack Detection Means) 32 Crack Detection Wiring 34 Crack Detection Wiring 110 Ozone generating element 134 Crack detection wiring A Discharge space

Claims (11)

[Claims] 1. A silent discharge type ozone generating element having a pair of discharge bodies, each of which has a metal electrode and is made of a ceramic layer that insulates the metal electrode from a discharge space, facing each other. An ozone generating element, characterized in that it is provided with a crack detection wiring arranged in the. 2. A creeping discharge type ozone generating element in which a linear discharge electrode and a planar induction electrode are integrally provided via a ceramic layer, wherein a crack detection wiring is provided in the ceramic layer. An ozone generating element characterized by being provided. 3. A silent discharge type ozone generator having a pair of discharge bodies made of ceramic layers, each having a metal electrode and insulating the metal electrode with respect to a discharge space, facing each other. An ozone generator comprising: a crack detection wiring disposed in the above; and a crack detection means for detecting a crack in the discharge body by disconnection of the crack detection wiring. 4. A creeping discharge type ozone generator in which a linear discharge electrode and a planar induction electrode are integrally provided via a ceramic layer, the crack detecting wiring being disposed in the ceramic layer. An ozone generator comprising: a crack detecting unit that detects a crack in the discharge body due to a break in the crack detecting wiring. 5. The ozone generating element according to claim 1, wherein the crack detection wiring is arranged between the metal electrode and the same ceramic layer so as to substantially surround the metal electrode. 6. The ozone generator according to claim 3, wherein the crack detection wiring is arranged between the metal electrode and the same ceramic layer so as to substantially surround the metal electrode. 7. The ozone generating element according to claim 1, wherein the crack detection wiring is arranged between a ceramic layer different from the metal electrode. 8. The ozone generator according to claim 3, wherein the crack detection wiring is arranged between a ceramic layer different from the metal electrode. 9. The ozone generating element according to claim 1, wherein the crack detection wiring is arranged on the surface of the ceramic layer. 10. The ozone generator according to claim 3, wherein the crack detection wiring is arranged on the surface of the ceramic layer. 11. The ozone generator according to claim 3, wherein one of the crack detecting means detects disconnection of the crack detecting wiring of the pair of discharge bodies connected in series.